Vegetarian Summer Tomato Sauce

The tomatoes have been so good lately that I thought I'd put up a big batch of sauce for those winter nights when I'm dying for summer produce. I bought several pounds of gorgeous, locally grown tomatoes the other day and made enough for an army! This is a mild sauce, and it would be really good with a little hot pepper thrown in if you like that. Also, you can add as many summer veggies as you want. I often use broccoli, but sometimes I think the flavor can be overwhelming.

About 2 Quarts diced fresh tomatoes (although you could easily use canned)
2 large bell peppers (I used yellow ones to make it extra summery), diced
2 Cups yellow summer squash, sliced (or just plain zucchini would also be yummy)
1 large sweet onion (Maui, Walla Walla or Vidalia), diced
3 cloves garlic, chopped fine
2 cans tomato paste
2 Tbs sugar
Marjoram
Basil
Thyme
Oregano
Olive Oil

Sautee the onion with the garlic in a little olive oil, until they are translucent. Add the tomatoes, peppers and herbs to taste. Remember, don't be shy with your herbs! They do so much for a slow-cooked sauce like this. Add the tomato paste. Bring to a boil and then simmer for about 45 minutes, stirring occasionally. Add the sugar and squash, and salt and pepper to taste. Let cook until the squash is softened, and then remove from heat. This makes a lot of sauce, so you should plan to can or freeze some of it.